Malicious PDF — malware analysis report

Static analysis result for SHA-256 fc735393d9015559…

MALICIOUS

PDF

83.9 KB Created: 2021-09-16 13:21:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: a203fa19d0dc57f3c64167230f736b86 SHA-1: 7dceb9b2db1236a15c89f306f730e2e0963b64c8 SHA-256: fc735393d9015559fd90d15e04ec933fda84dab59ef5dd736c8459965d61d3a1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains numerous links, many of which point to disposable hosting or compromised CMS upload storage, indicating a link farm designed to mislead users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links. No scripts were extracted, and the document body was unreadable, so the rationale is based on the PDF-specific heuristics and URL analysis.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://northcity.rs/slike/files/bugelogasanomudalobaz.pdf In PDF document text
    • https://adverto.ee/userfiles/file/ladawudixutopedenof.pdfIn PDF document text
    • https://webhosting4.net/media/file/lobagepuzugamugupevu.pdfIn PDF document text
    • http://acm-medicali.it/userfiles/files/70794726944.pdfIn PDF document text
    • http://manilag.com/FileData/ckfinder/files/20210909_509E0C8AF7775598.pdfIn PDF document text
    • https://futurefacesnyc.com/uploads/file/16757116404.pdfIn PDF document text
    • http://ibookingkr.com/FileData/ckfinder/files/20210902_A8AFC8282497A326.pdfIn PDF document text
    • https://serpavenger.com/ckfinder/userfiles/files/15366951752.pdfIn PDF document text
    • http://minhtoangalaxyhotel.vn/app/webroot/files/ckfinder/files/44555497749.pdfIn PDF document text
    • http://bellezaeimagen.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1613214bbb6e6f---41873161291.pdfIn PDF document text
    • http://dooroc.com/tk/upload/file/75485681321.pdfIn PDF document text
    • http://dostrojar.sk/UserFiles/file/zowatewidewarozaxitog.pdfIn PDF document text
    • http://etnorom.hu/pictures/60909564880.pdfIn PDF document text
    • http://tko.wavedev.net/img/files/files/51925702510.pdfIn PDF document text
    • https://limblength-sldf.com/userfiles/file/xizebevusiwudokenomixe.pdfIn PDF document text
    • https://immsac.pe/sgi_userfiles/userfiles/files/34062351537.pdfIn PDF document text
    • https://www.actionconstructionjax.com/wp-content/plugins/super-forms/uploads/php/files/c350ef39e16c1ec150ef7823e9ec834c/82710764759.pdfIn PDF document text
    • http://francescasciortino.it/userfiles/files/14476054165.pdfIn PDF document text
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/1614153c790471---nadalalirexobizobovuge.pdfIn PDF document text
    • https://abyway.lv/images/ck_images/files/6285088037.pdfIn PDF document text
    • http://wiskind.com/filespath/files/20210912142111.pdfIn PDF document text
    • http://acmemask.com/upfiles/editor/files/77252548491.pdfIn PDF document text
    • https://magatek.com/documents/file/wumudufupofutid.pdfIn PDF document text
    • http://s8radziejowice-paszkow.pl/userfiles/file/59675028510.pdfIn PDF document text
    • http://mmbc.cz/_data/user_files/file/xoxib.pdfIn PDF document text
    • http://olgapolyakova.de/files/files/76496839989.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=how+to+get+minecraft+on+android+tabletPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e323.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE323 17648 bytes
SHA-256: fdd3dfb65f1452930a45281d2fa4cbd4008bcad7bb4202d7d0eadc2a7c121c80
font_01_sfnt_off000110f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110F0 10868 bytes
SHA-256: d428335550bd39fd5b341726de76ae9924f22838fe642dc16f1fcaa10d79df85
font_02_sfnt_off000129d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129D6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1